package cn.aixuxi.notebank.aop;

import cn.aixuxi.notebank.authc.JwtToken;
import cn.aixuxi.notebank.constant.DefConstant;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.RequestMethod;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 类描述 Jwt过滤
 *
 * @author ruozhuliufeng
 * @version 1.0
 * @date 2020/11/15 21:18
 */
public class JwtFilter extends BasicHttpAuthenticationFilter {

    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
        try{
            executeLogin(request,response);
            return true;
        }catch (Exception e){
            throw new AuthenticationException("Token失效，请重新登录", e);
        }
    }

    @Override
    protected boolean executeLogin(ServletRequest request, ServletResponse response) throws Exception {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        String token = httpServletRequest.getHeader(DefConstant.ACCESS_TOKEN);
        JwtToken jwtToken = new JwtToken(token);
        // 提交给Realm进行登录，如果错误会抛出异常并被捕获
        getSubject(request, response).login(jwtToken);
        // 如果没有抛出异常则代表登入成功，返回true
        return true;
    }

    /**
     * 功能描述: 对跨域提供支持
     * @param request 1
     * @param response 2
     * @return : boolean
     * @author : ruozhuliufeng
     * @date : 2020/11/15 21:30
     */
    @Override
    protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
        httpServletResponse.setHeader("Access-control-Allow-Origin",httpServletRequest.getHeader("Origin"));
        httpServletResponse.setHeader("Access-control-Allow-Methods","GET,POST,OPTIONS,PUT,DELETE");
        httpServletResponse.setHeader("Access-control-Allow-Headers",httpServletRequest.getHeader("Access-control-Request-Headers"));
        // 跨域时会首先发送一个option请求，这里我们给option请求直接返回正常状态
        if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name())){
            httpServletResponse.setStatus(HttpStatus.OK.value());
            return false;
        }
        return super.preHandle(request, response);
    }
}
